/*! ========================================================================
** Extended Template Library
**
** Copyright (c) 2002 Robert B. Quattlebaum Jr.
**
** This package is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public License as
** published by the Free Software Foundation; either version 2 of
** the License, or (at your option) any later version.
**
** This package is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
** General Public License for more details.
**
** === N O T E S ===========================================================
**
** This is an internal header file, included by other ETL headers.
** You should not attempt to use it directly.
**
** ========================================================================= */

#ifndef __ETL__REF_COUNT_H
#define __ETL__REF_COUNT_H

#include "_curve_func.h"
#include <cassert>

_ETL_BEGIN_NAMESPACE

class weak_reference_counter;

/*!	\class	reference_counter	_ref_count.h	ETL/ref_count
**		Reference counter
**	\see weak_reference_counter
**	\writeme
*/
class reference_counter
{
    friend class weak_reference_counter;
private:
    int* counter_;
public:

    reference_counter(const bool &x = true): counter_(x ? new int(1) : 0) { }

    reference_counter(const reference_counter &x): counter_(x.counter_)
    {
        if (counter_) {
            (*counter_)++;
        }
    }

    reference_counter(const weak_reference_counter &x);

    ~reference_counter()
    {
        detach();
    }

    reference_counter& operator=(const reference_counter &rhs)
    {
        detach();
        counter_ = rhs.counter_;

        if (counter_) {
            assert(*counter_ > 0);
            (*counter_)++;
        }

        return *this;
    }

    void detach()
    {
        if (counter_) {
            assert(*counter_ > 0);

            if (!--(*counter_)) {
                delete counter_;
            }

            counter_ = 0;
        }
    }

    void reset()
    {
        detach();
        counter_ = new int(1);
    }

    int count()const
    {
        return counter_ ? *counter_ : 0;
    }

    bool unique()const
    {
        return counter_ ? *counter_ == 1 : 0;
    }

    operator int()const
    {
        return count();
    }
}; // END of class reference_counter

/*!	\class	weak_reference_counter	_ref_count.h	ETL/ref_count
**		Weak Reference counter
**	\see reference_counter
**	\writeme
*/
class weak_reference_counter
{
    friend class reference_counter;
private:
    int* counter_;
public:
    weak_reference_counter(): counter_(0) { }

    weak_reference_counter(const weak_reference_counter &x): counter_(x.counter_) { }

    weak_reference_counter(const reference_counter &x): counter_(x.counter_) { }

    ~weak_reference_counter() { }

    weak_reference_counter& operator=(const reference_counter &rhs)
    {
        counter_ = rhs.counter_;
        assert(*counter_ > 0);
        return *this;
    }

    weak_reference_counter& operator=(const weak_reference_counter &rhs)
    {
        counter_ = rhs.counter_;
        assert(*counter_ > 0);
        return *this;
    }

    void detach()
    {
        counter_ = 0;
    }

    int count()const
    {
        return counter_ ? *counter_ : 0;
    }

    bool unique()const
    {
        return counter_ ? *counter_ == 1 : 0;
    }

    operator int()const
    {
        return count();
    }
}; // END of class weak_reference_counter

inline reference_counter::reference_counter(const weak_reference_counter &x):
    counter_(x.counter_)
{
    if (counter_) {
        (*counter_)++;
    }
}

_ETL_END_NAMESPACE

#endif